Air quality in an environment may change before, during, and after various events. For example, in an indoor environment such as an office or one or more rooms of a home or apartment, levels of some types of pollutants may increase when certain appliances (e.g., vacuum cleaners, washers, dryers, stoves, ovens, grills, griddles, microwaves, etc.) are operated. Levels of some types of pollutants may increase when the indoor environment is exposed to an external environment by, for example, a window or door being opened. For example, pollutants typically associated with outdoor sources (e.g., some types of particles, smog) may be present at higher levels in a home when one or more windows are open. Some types of pollutants may be present at increased levels when an occupant is performing an activity that may introduce pollutants into the indoor environment, such as smoking, painting, etc. Operating an air purifier without regard to the changes in air quality caused by these various events may lead to overconsumption of power and/or unnecessary wear and tear on the air purifier and/or one or more incorporated air filters. Even operating an air purifier in response to detected changes in air quality caused by these various events may not be sufficient to prevent durations of unacceptable air quality.